Experimental evaluation on the applicability of necrobiome analysis in forensic veterinary science

Abstract

Despite the wide usage of animals as models in forensic studies, the investigations of fundamental legal questions involving domesticated and nondomesticated animals were always given marginal attention compared to “human forensic,” and only recently the interest in the discipline is increasing. Our research focuses on the effect of the fur coat on the activity and development of microbial decomposers. In order to test this variable never assessed before, rabbit carcasses were used and results show that: (i) distinct and significant temporal changes in terms of metabolic activity and taxa distribution can be tracked over the decomposition process; (ii) the richness and the diversity of the bacterial communities does not significantly vary over time, but it does not mean that the species Operational Taxonomic Units (OTUs) do not change; (iii) the presence/absence of the fur on the carcasses does not significantly affect either the bacterial communities’ functional activity or the diversity intra‐ and intercommunity, neither at phylum nor at family resolution; (iv) the functional activity and the ecological diversity of the bacterial communities are significantly affected by the body region, while the relative abundance is not. Obtained data confirm previous observations and provide new insight in the Forensic Veterinary field in terms of equally using them in order to derive a statistical model for the PMI estimation. As a future perspective, a contribution to the Forensic Entomology approach will be given in legal investigations when domestic or wild animals are involved, regardless of the presence of a hair layer.

Avoidance of carnivore carcasses by vertebrate scavengers enables colonization by a diverse community of carrion insects

“…Therefore, if site-specific succession patterns are known, a minimum post-mortem interval may be estimated in a forensic case on the basis of the entomofauna present on the cadaver [21]. In a similar way, some studies have also explored the potential of the changes in the bacterial communities during the decomposition process of animal carcasses as indicators for death time estimations in forensic veterinary science [23]. However, two important caveats undermine current scientific understanding of carrion consumption in natural conditions, as indicated below.…”

Innovations in Forensic Sciences for Human Identification by DNA in the French Gendarmerie during the Last 10 Years

“…They are highly specific and can be used to differentiate and classify the originating body site of a human biological trace. Skin microbiota is also highly specific and different between individuals, leading to its potential as an identification tool [65]. By extension, the possibility of microbial communities being deposited on everyday objects has also been explored.…”

Microbial DNA in human nucleic acid extracts: Recoverability of the microbiome in DNA extracts stored frozen long-term and its potential and ethical implications for forensic investigation

“…Besides these two indicator species, we observed additional taxa that are highly abundant in the burnt samples, including Vulcaniibacterium (Gammaproteobacteria, Xanthomonadaceae), Escherichia-Shigella (Gammaproteobacteria, Enterobacteriaceae), Pseudomonas (Gammaproteobacteria, Pseudomonadaceae), Methylobacterium-Methylorubrum (Alphaproteobacteria, Rhizobiales), Aeribacillus (Bacilli, Bacillaceae), Romboutsia (Clostridia, Peptostreptococcaceae), Paraclostridium (Clostridia, Peptostreptococcaceae) and Clos-tridium_sensu_stricto_1 (Clostridia, Clostridiaceae). Some of these taxa have been frequently reported to be associated with decomposing remains and carcasses (i.e., Pseudomonadaceae, Xanthomonadaceae, Enterobacteriaceae [1,44,49,[86][87][88]). Vulcaniibacterium, similarly to Pyrinomonas, has been isolated from a geothermally heated soil samples [88], and their presence in charred samples is therefore not completely unexpected.…”